Fig. 6. Changes in arterial pressure a (A) and heart rate fH (B) during acute exposure to 10%O₂ in the three experimental groups (white bars, N21, normoxic incubation; grey bars, H15, 15%O₂ incubation; black bars, H10, 10%O₂ incubation) at different incubation ages. The changes were calculated by subtracting the values during hypoxia from the control values. ^*Significant difference from N21. Values are means ± S.E.M. For N values, see Table 1.